21 DIAGNOSISAlthough the diagnosis of SCC is often strongly suspected based on clinical findings, a skin biopsy is required for definitive diagnosis.A shave biopsy, punch biopsy, incisional biopsy, or excisional biopsy, wedge biopsy may be used.All skin biopsy samples obtained to diagnose SCC must reach at least the depth of the mid dermis to allow for determination of the presence or absence of invasive disease.

28 FOLLOW UPLow-risk tumors are usually cured with appropriate surgical therapy; recurrence may occur.Thus, patients with a history of SCC should be evaluated with a complete skin examination every 6-12 months.Patients with high-risk tumors require skin and lymph node examinations at 3- to 6-month intervals for at least 2 years after diagnosis.

33 Development of Nevi Junctional nevi Compound nevi Dermal nevinests along dermal-epidermal junctionCompound nevi“invade” dermis, first as nests then cords and single cellsDermal nevijunctional component lost only in papillary and reticular dermisHistologically, nevi are classified generally as having atypical cells, as in dysplastic nevi, or normal cytology, as in the common nevus.

45 Acral lentiginous melanomaOccurs in palms,soles and subungual areasWorse prognosis than superficial spreadingPigment spread to the proximal or lateral nail folds is termed the Hutchinson sign, which is a hallmark for acral lentiginous melanoma.

46 AMELANOTIC MELANOMAAppear pink but close inspection reveals pigmentationLack of pigmentation causes delay in diagnosis.Worst prognosis of all melanomas

49 Diagnosis Excision biopsy of suspected lesions mainstay of diagnosisPerformed with 1-2mm margin and has to be full thickness to ascertain the following:Tumor thickness (Breslow depth)Presence of ulcerationAnatomic level of invasion (Clark level)Presence of mitosesPresence of regressionLymphatic/vessel invasion or vascular involvementHost response (tumor-infiltrating lymphocytes)